What are the tips for recovering a DB2 database through redirection?

The following articles mainly describe how to use redirection to restore a DB2 database. If you are curious about using redirection to restore a DB2 database, the following articles will unveil its secrets. The following is a detailed description of the article.

The DB2 database Restoration Operation uses the database backup image to recreate the database. To clone a database from one machine to another, the simplest way is to restore the database from the backup image.

The DB2 database Restoration Operation uses the database backup image to recreate the database. To clone a database from one machine to another, the simplest way is to restore the database from the backup image. The file system path used by the database is also included in the backup image. Therefore, unless the file system and physical devices referenced by the database on the source system are set in the same way as those of the target system, you need to perform the redirection to recover DB2.

Tip: If DB2 V8 is available, you can obtain a backup from any high-priority server and restore it to any other high-priority server. For example, you can restore a backup image from DB2 for HP-UX to DB2 for AIX®Or Sun Solaris. However, this does not apply to Windows and Linux.

The redirection recovery operation includes two steps for the database to recover the DB2 database, and there is a tablespace container definition step in the middle:

Issue the restore database command with the REDIRECT option.

Use the set tablespace containers command to define the TABLESPACE container of the recovered database (DB2 needs to know where you want the TABLESPACE to reside on the target system ).

Issue the restore database command again, and specify the CONTINUE option this time.

The whole redirect recovery operation must be called in the same session; otherwise, SQL0900N will be returned, and the recovery operation will fail. Remember this is important. One way to avoid this is to create and run a script that contains all three parts of the Redirect recovery process.

The following (Windows) example shows how to successfully perform the redirection to restore DB2. I will demonstrate how to restore the DB2 database backup image from different instances, rather than from another server. The principle is the same, and the details are the same.

The source Instance name in this example is PROD. The name of the target instance is MYINST. The name of the existing database on the PROD to be restored (created) on MYINST is MOVIES. The MOVIES database is on the D disk.

Create a complete database backup image for the MOVIES database on PROD:

 
 

  
  
setDB2INSTANCE=PRODdb2   
  
  
startdb2   
  
  
backupdbmovies  
 
 

The time stamp of this image is 20021006213640, and the image is in D: movies?prodnode=catn=20021006. DB2 creates this subdirectory tree in the directory where the backup database command is issued. The subdirectory name indicates the following meanings:

In this subdirectory tree, there will be a file (213640.0) indicating the actual backup image ). The file name indicates the time when the backup was obtained.

Create a similar path (replace PROD with MYINST ):

 
 

  
  
md MOVIES.0MYINSTNODE0000CATN000020021006 
 
 

This is a key step: If this path is not correctly created, subsequent database recovery operations will fail. If you are re-locating the backup image to another machine, create the above path on the target machine (replace MYINST with the appropriate target Instance name ), and copy the backup image (213640.0 in this case) to this directory. You can also use a compression tool to package backup images when maintaining the directory tree for transmission.

Start MYINST, and then call the redirection to restore the DB2 database.

The above content is an introduction to the use of redirection to restore the DB2 database. I hope you will have some gains.